The 31-year-old country star, who grew up on a farm and has maintained vegetarian and vegan diets since she was a teenager, told Yahoo! Beauty in an interview posted on Tuesday that she will continue to remain meat-free during her pregnancy. The Grammy winner and American Idol alum and husband Mike Fisher, a 34-year-old NHL player, are expecting their first child, a baby boy.

"I have been vegetarian for about 10 years now," she said. "With pregnancy, I am definitely going more on the vegetarian side, but as soon as I am not pregnant anymore I will go back to being vegan."

Maintaining a vegetarian diet while pregnant is healthy for both mothers and their children as long as the women get the appropriate vitamins and nutrients. Doctors may prescribe supplements.

Pregnant women also require more protein in the second and third trimesters, according to the Physicians Committee for Responsible Medicine. Therefore, lacto-vegetarians, who consume dairy, and lacto-ovo vegetarians, who also eat eggs, may find it easier to maintain a healthy pregnancy diet than vegans.

Expectant mothers who refrain from eating meat, fish and eggs are encouraged to consume other foods rich in iron, such as leafy vegetables and grains to minimize the risk of anemia, which can lead to birth defects. Vegan and vegetarian pregnant women are also at a higher risk of becoming deficient in vitamin B-12, which is found in animal-based proteins and milk but also in certain soy products.

This past September, Underwood was spotted giving into a non-vegan craving of her own—she was seen picked up a pint of Ben & Jerry's vanilla ice cream, which is made with cream, skim milk and egg yolks.

"I don't think I am craving anything too crazy," the singer told Yahoo! Beauty. "I try to keep it as healthy as possible and try to take care of myself. And, you know, putting good things in!"

Underwood grew up in Oklahoma on a farm. Her family raised cattle. She told the Australian morning show The Circle in 2011 that she stopped eating red meat when she was "about 13."

"There was a traumatic incident that made me stop eating beef," she told Women's Health magazine in 2007. "My parents were banding cattle. When I asked why, I was told that it makes them bigger. And it hit me that these cute little animals that were running around playing would become someone's dinner. Eating them made me feel guilty."

Oklahoma lists beef and pork among its top five agriculture exports. Milk was designated the official state drink in 2002. In 1988, local lawmakers declared the components of the Oklahoma Official State Meal, which isn't extremely healthy; it includes barbecued pork, chicken-fried steak and sausage with biscuits and gravy.

"Living in Oklahoma, it's almost impossible to be vegetarian, so when I kinda moved away, I was about 21, I became vegetarian and recently made a switch to vegan because I'm actually kind of, like, lactose-intolerant," she said on The Circle.

Underwood's family members, including her husband, have not followed her lead. No Tofurkeys for them!

"It makes for an interesting Thanksgiving," Underwood told Women's Health. "At first it was really difficult. My mom would get so mad at me. But now, she's accepted it. Everything she used to make with cream of chicken soup, she now makes with cream of mushroom soup."